The present invention relates to a ribbon cartridge and an adapter for effecting the loading of same.
Ribbon cartridges for typewriters and word processing equipment are well known and have a variety of outward configurations and internal mechanisms, depending upon the machine in which they are to be used. A common problem that occurs in the use of ribbon cartridges, especially of the single use ribbon cartridge, is the maintaining of a proper tension on the ribbon so that the ribbon does not jam during its advance and such that the ribbon is effectively and efficiently utilized by the printing equipment.
The current state of the art in ribbon cartridges effects the tensioning of the ribbon by providing a soft sponge-like member on one of the inner flat surfaces of the ribbon cartridge which extends radially with respect to the ribbon at the supply side of the cartridge and which contacts the ribbon during use to exert a frictional force on the ribbon which prevents the ribbon from freely rotating while not preventing advancement of the ribbon by the printing mechanism.
At the same time, a tensioning mechanism in the form of a spring or the like biases the ribbon at the supply side of the cartridge and before the ribbon extends through the outlet of the cartridge so that the ribbon is properly taut during its use. The advancing mechanism acting on the take-up spool or transmission mechanism of the ribbon works in conjunction with the tensioning member to keep the ribbon taut during advancement and use.
The friction applying member of the prior art has the disadvantage of exerting an uneven force on the ribbon spool during use since the sponge-like member is directed radially across the ribbon spool and thus as the ribbon spool unwinds, the force exerted on the spool decreases. Moreover, the adding of the sponge-like member to the cartridge housing becomes expensive due to the fact that the cartridge housing, conventionally made of a single piece of molded plastic, necessitates the further manual manufacturing operation of applying an adhesive and placing the sponge-like member in its proper location.
Other conventional cartridges are known which have a substantially rectangular configuration and wherein the ribbon inlet and outlet apertures are spaced a substantial distance from the feed mechanism for the particular printing mechanism of the typewriter or word processing apparatus. In use, after the cartridge is mounted in place in the apparatus, the user must thereafter manually guide the ribbon into the printing mechanism, usually resulting in a loss of time and the soiling of the users hands.